1. Field of the Invention
The present invention relates to waste management systems which process recyclable materials.
2. Description of the Related Art
In recent years, high priority has been given to the task of conserving natural resources while at the same time reducing the amount of waste which is transferred to landfills and other dump sites. In fact, the reduction of waste has become such a high priority that, in some states, legislation has been passed which mandates the reduction of waste that is transferred to landfills by as much as 50%. One way of accomplishing this goal is to increase the percentage of goods which are recycled in proportion to the total volume of refuse.
In previous refuse recycling systems, a flow of refuse is usually transported by a conveyor or similar means past a number of operators who manually extract recyclable materials from the flow of refuse. Each operator is assigned a particular kind of recyclable material (e.g., newspapers, plastics, glass, etc.) which that operator extracts from the refuse flow. The operators are positioned proximate to one or two chutes which lead to separate deposit banks, so that the operators are able to deposit the extracted recyclable materials into the chutes proximate to their position. Each chute is generally designated to receive only one kind of recyclable material so that each deposit bank accumulates only one type of material. The materials in each deposit bank are then packaged and transported to the appropriate recycling facilities. The materials which are not recovered from the refuse flow are typically transferred to a landfill or other waste disposal site.
The physical layout of such systems usually includes a conveyor belt which runs directly in front of the operator so that it is easy for the operator to identify and extract the appropriate materials. The chute or chutes are then typically positioned to the immediate right and/or left of the operator, and are generally made to have a relatively large receiving orifice, so that the operator can quickly deposit the extracted materials without having to turn and see where the extracted material is to be placed. This is important since, in the time it takes for an operator to turn and locate a chute, it is possible that a quantity of recyclable material which that operator might otherwise have extracted could pass out of reach of the operator, thereby decreasing the efficiency of the system. In addition, the necessity of turning back and forth between the conveyor and the deposit chute could contribute to operator fatigue.
Since it is important that the chutes be relatively large, and located proximate to the operator, additional chutes would have to be positioned somewhat behind the operator in conventional systems. This is disadvantageous because the operator would be required to turn around while depositing goods into those chutes. Thus, in order to preserve efficiency in such a system, each operator is effectively limited to two chutes.
Because each operator is effectively limited to two chutes, and each chute typically receives only one type of recyclable material, the number of types of recyclable materials recovered in such systems is usually limited. This is because it is often costly to employ additional operators and to construct additional recovery stations. Thus, waste management facilities are often reluctant to increase their operating costs in order to recover additional kinds of recyclable materials. As a result, certain kinds of recyclable materials are not recovered by facilities which use the previous systems described above. This, in turn, results in an increase in the amount of material which is transferred to landfills. In addition, this results in a greater consumption of natural resources because goods which could otherwise have been recycled are instead wasted.
Thus, a need exists for a refuse recycling system which provides for increased recovery of recyclable materials without compromising operator efficiency and without increasing operating costs.
In addition to the aforementioned shortcomings of previous waste management systems, certain other limitations exist with conventional refuse recycling systems. These further limitations are due, in part, to the inability of these systems to effectively distinguish between certain species of refuse. Refuse which is delivered to recycling facilities typically comes from two major sources: commercial and residential. It has been found that the proportions between the types of recyclable materials in commercial refuse is generally different from the proportions between the types of recyclable materials in residential refuse. Thus, to optimize the efficiency of a recycling system, it may be advantageous to alter the operation of the recycling system in accordance with the species of refuse (e.g., commercial or residential) which are delivered to the system. Most systems, however, do not alter their operation in accordance with the species of refuse which are delivered to them. This may oftentimes lead to processing inefficiencies and an increase in the amount of waste produced by such systems.
Thus, a further need exists for a refuse recycling system which may be controlled to increase processing efficiency in response to the introduction of different species of refuse.